Well, if it was just taking care of the babies she could do it I think on her own but as the baby need that whatchamacallit magic from dad which she can't give and without it worse could happen to the babies then I see this as no other choice and MC is a decent guy so I saw him taking responsibility/pity from a mile away.
Also, they aren't alone in this. Seems like many other will support them any other way possible(MC's family).
Way different then most irl cases people talking about down comments.